The number of bacteria in a certain culture doubles every hour. If there were 30 bacteria present in the culture originally, how many bacteria will be present at the end of 2nd hour, 4th hour and nth hour?

Asked by Abhisek | 1 year ago |  109

Solution :-

Given, the number of bacteria doubles every hour. Hence, the number of bacteria after every hour will form a G.P.

Here we have, a = 30 and r = 2

So, a3 = ar2 = (30) (2)2 = 120

Thus, the number of bacteria at the end of 2nd hour will be 120.

And, a5 = ar4 = (30) (2)4 = 480

The number of bacteria at the end of 4th hour will be 480.

an +1 = arn = (30) 2n

Therefore, the number of bacteria at the end of nth hour will be 30(2)n.

Answered by Abhisek | 1 year ago

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